The teeth of a modern human (left) and the skull of an extinct mammal, called an oreodont, that looked like a sort of sheep-pig hybrid

How do paleontologists know what most 8-year-olds know: that Tyrannosaurus rex ate meat and Brachiosaurus ate plants?

A recent exhibition at the Amherst College Museum of Natural History answered that question. “In the absence of being able to observe something feeding,” says Kate Wellspring, the museum’s collections manager, “paleontologists rely on different clues.” Those clues range from tooth size and shape, to preserved stomach contents, to something certain to mesmerize any elementary school kid: coprolites, which are pieces of fossilized feces.

Visitors to the Tell Me What You Eat exhibition, which ran in late fall and early winter, learned that, when studying long-extinct animals, scientists look for direct evidence—bits of food preserved within an animal’s teeth, perhaps (dinosaurs weren’t daily flossers)—and indirect evidence, such as coprolites. “With sharks, you often find fish scales preserved inside of them,” Wellspring says. “Even after 30 million years, you can still identify a fish scale.”

It wasn’t just any coprolite on display for this special exhibit, but a copy of one of the largest ever found. On loan from the Royal Saskatchewan Museum in Canada, this lumpy specimen, some 18 inches long and 7 inches tall, is likely from a T. rex. “They’d made a plaster cast of it,” Wellspring says, “and that’s what I borrowed. It’s painted, so it’s almost indistinguishable from the original.”

Among the other items on display were a cast of a T. rex skull, including pointy teeth ideal for killing and eating animals, and a hippopotamus skull, with “giant, menacing-looking tusks” and “great big molars,” Wellspring says.

Visitors learned that while the tusks are for display, the molars are for grinding up vegetation. At a microscope station, children and adults examined casts of animal teeth for tiny markings that reveal what those animals ate in the days before they died.

Tell Me What You Eat, one of many food-themed exhibitions from the local Museums 10 consortium, was especially well-received by children dropping in with their parents or grandparents. “Little kids in particular are always curious about which dinosaurs ate meat and which ate plants,” Wellspring says. “It’s endlessly fascinating.”